Updated July 1, 2026
Time zones reference
A quick lookup of common time zones and their standard (non-daylight-saving) UTC offsets. Many regions shift by an hour for part of the year, so treat these as the baseline and convert with the daylight-saving rules applied.
Common zones (standard time)
| Zone | Abbr. | Standard offset |
|---|---|---|
| Coordinated Universal Time | UTC | +00:00 |
| Greenwich Mean Time | GMT | +00:00 |
| US Eastern | ET (EST) | -05:00 |
| US Central | CT (CST) | -06:00 |
| US Mountain | MT (MST) | -07:00 |
| US Pacific | PT (PST) | -08:00 |
| Central European | CET | +01:00 |
| Eastern European | EET | +02:00 |
| India Standard | IST | +05:30 |
| China Standard | CST | +08:00 |
| Japan Standard | JST | +09:00 |
| Australian Eastern | AET (AEST) | +10:00 |
UTC vs GMTUTC and GMT share the same +00:00 offset and are often used interchangeably, but UTC is the modern, precise time standard while GMT is a time zone. Prefer UTC when accuracy matters.
Daylight saving shifts theseRegions that observe daylight saving move an hour for part of the year (US Eastern goes from -05:00 to -04:00), and change dates differ by country. Convert with a tool that applies the current rules rather than a fixed offset.
References
Questions
What is the difference between UTC and GMT?
They point to the same clock time (+00:00), but UTC is a precise time standard based on atomic clocks, while GMT is a time zone. In everyday use they are treated as equivalent.
Why do time zone offsets change during the year?
Because of daylight saving time. Many regions advance their clocks an hour in warmer months and revert in cooler ones, so their UTC offset changes for part of the year.